While if I ever got to the point of being pretty fabulously wealthy I suspect I'd quite like to give a bit of money to my friends and family I can easily understand that it might present a dilemma to them at the same time - there might be a feeling that you're trying to buy friendship or that they'll then owe you something, it's almost certainly not the intention here for you to feel like that but it can be very difficult to rationalise feelings.
I don't know what I would do if I was given £10k by a friend, I'd appreciate that they were trying to help me and share the wealth so to speak but I think I might well feel obligated to give it to charity - I've done nothing much to deserve the money, I'd be friends with them regardless and provided I didn't desperately need the money at the time I imagine there are plenty of other people who do need it more than me. There's no right or wrong here, it's based on how you (and your wife) feel.